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by hdhzy 3349 days ago
In JavaScript it depends on how it is invoked: eval(a) has access to scope variables but x=eval;x(a) does not.
1 comments
Gaelan 3349 days ago
I am surprised that JavaScript can still surprise me.
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hdhzy 3349 days ago
I suggest reading the spec. 5.1 [0] although dated is written in very easy to understand language (well, most parts).

After that, fragments like this suddenly make sense:

    n = 1
    /1*"\/\//.test(n + '"//')
[0]: https://www.ecma-international.org/ecma-262/5.1/
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Gaelan 3348 days ago
My favorite bit of wat.js is this:

    [1,2,3] + [4,5,6] // => "1,2,34,5,6"
I mean, it makes some degree of logical sense (toString -> concat) but there is no reason that would ever be the intended behavior.

As for that expression, meh. You can write intentionally obtuse code in any language. The problem with JS is the behavior that is different from what you'd expect.

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